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Multiplying Fractions

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    We're asked to multiply 5/6
    times 2/3 and then simplify
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    our answer.
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    So let's just multiply
    these two numbers.
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    So we have 5/6 times 2/3.
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    Now when you're multiplying
    fractions, it's actually a
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    pretty straightforward
    process.
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    The new numerator, or the
    numerator of the product, is
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    just the product of the two
    numerators, or your new top
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    number is a product of the
    other two top numbers.
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    So the numerator in our product
    is just 5 times 2.
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    So it's equal to 5 times 2 over
    6 times 3, which is equal
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    to-- 5 times 2 is 10 and
    6 times 3 is 18, so
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    it's equal to 10/18.
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    And you could view this as
    either 2/3 of 5/6 or 5/6 of
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    2/3, depending on how you
    want to think about it.
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    And this is the right answer.
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    It is 10/18, but when you look
    at these two numbers, you
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    immediately or you might
    immediately see that they
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    share some common factors.
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    They're both divisible by 2,
    so if we want it in lowest
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    terms, we want to divide
    them both by 2.
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    So divide 10 by 2, divide 18 by
    2, and you get 10 divided
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    by 2 is 5, 18 divided
    by 2 is 9.
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    Now, you could have essentially
    done this step
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    earlier on.
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    You could've done it actually
    before we did the
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    multiplication.
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    You could've done
    it over here.
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    You could've said, well, I have
    a 2 in the numerator and
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    I have something divisible by 2
    into the denominator, so let
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    me divide the numerator by
    2, and this becomes a 1.
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    Let me divide the denominator
    by 2, and this becomes a 3.
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    And then you have 5 times 1
    is 5, and 3 times 3 is 9.
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    So it's really the same thing
    we did right here.
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    We just did it before we
    actually took the product.
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    You could actually
    do it right here.
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    So if you did it right over
    here, you'd say, well, look, 6
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    times 3 is eventually going
    to be the denominator.
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    5 times 2 is eventually going
    to be the numerator.
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    So let's divide the numerator by
    2, so this will become a 1.
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    Let's divide the denominator
    by 2.
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    This is divisible by 2,
    so that'll become a 3.
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    And it'll become 5 times 1
    is 5 and 3 times 3 is 9.
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    So either way you do
    it, it'll work.
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    If you do it this way, you get
    to see the things factored out
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    a little bit more, so it's
    usually easier to recognize
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    what's divisible by what, or you
    could do it at the end and
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    put things in lowest terms.
Title:
Multiplying Fractions
Description:

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Video Language:
English
Duration:
02:26

English subtitles

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